Portsmouth keeper David James fears their European commitments could impact on their Premier League ambitions.
Pompey sealed a place in the Uefa Cup by winning the FA Cup final against Cardiff last May after another successful campaign at Fratton Park.
Hopes are high for more succees ahead of the new campaign, but James believes the demands of Europe could stretch the Pompey squad to the limit.
"We've a Uefa Cup bid and that's going to put a strain on us with the amount of games and the size of our squad," James told The Mirror.
"Middlesbrough proved in 2006 you can go so far in the Uefa Cup but unless you win it, it becomes a bit of a fruitless task.
"It's going to be important we keep our players fit to do well in Europe and on the other front to do well in the league."
FocusEngland ace James fears further cup success this season could see Portsmouth take their eye off the ball in the league like they did in the final few weeks of last term when they lost their closing four games.
"As we found in the FA Cup last season it is easy to take your eye off your league position," added James.
"Arguably we could have finished fifth, but with the FA Cup we didn't and we ended up eighth."